AU
B1760

DTC B1760 indicates the SRS (Supplemental Restraint System) control unit detects the Left Front Side Curtain Airbag in a "not present" state — Atto 8

Safety System

DTC B1760 indicates the SRS (Supplemental Restraint System) control unit detects the Left Front Side Curtain Airbag in a "not present" state.

This means the ECU cannot identify the airbag electrical circuit during the self-check, or detects an open circuit or abnormal resistance (normal resistance is approximately 2-5Ω).

The side curtain airbag (CAB) mounts inside the roof side rail and protects occupant heads during a side impact or rollover.

This level 2 safety system fault prevents the left front side curtain airbag from deploying during a collision and continuously illuminates the instrument cluster airbag warning light.

On certain BYD models (such as the Song MAX and Qin petrol version), this fault code may also indicate a driver seat position sensor circuit fault.

The SRS uses seat position data to determine the airbag deployment strategy; a failed sensor can cause the system to log a similar code.

The B1760 fault code on the Atto 8 indicates the SRS control unit cannot detect the left front side curtain airbag, often due to an open circuit or abnormal resistance. This medium-severity fault may stop that airbag deploying and keeps the airbag warning light on. Common causes include damaged wiring near pillar connectors or a loose, corroded, or wet airbag connector. Visit an authorised dealer for diagnosis and repair. Typical repair cost data is available.
5
Cases Logged
5
Causes
Likely Causes — Atto 8
  • 1Open or short circuit in left front side curtain airbag wiring harness (commonly at A-pillar or B-pillar harness connectors, or wear on harness routed under the seat)
  • 2Airbag connector loose, terminal backed out, oxidized, or water ingress (especially inline connectors below the A-pillar, inside the headliner, or under the seats)
  • 3Open circuit or abnormal resistance in the airbag module internal squib circuit (normal resistance: 2-5 Ω; values outside this range report as not present).
  • 4SRS ECU internal fault or software version defect causing false detection
  • 5Vehicle wading causing water ingress and oxidation of wiring harness connectors, or incorrect wiring harness reconnection after seat modification or headliner removal.
What To Do
  • 1
    Use a BYD VDS or Launch X-431 diagnostic tool to read freeze frame data and confirm vehicle status, ambient temperature, and voltage conditions when the fault occurred.
  • 2
    Switch off the ignition, disconnect the battery negative terminal, and wait at least 90 seconds to fully discharge the SRS system and prevent accidental airbag deployment.
  • 3
    Visually inspect the left front side curtain airbag connector (located below the A-pillar, inside the headlining trim panel, or under the seat) for looseness, corrosion, terminal back-out, or water ingress.
  • 4
    Use a multimeter to measure the airbag circuit resistance: Disconnect the SRS ECU connector and measure the resistance from the wiring harness side to the airbag. The resistance must be between 2-5 Ω. (Measure through an adapter plug. Do not measure directly at the airbag connector to prevent static electricity from triggering deployment.)
  • 5
    Check wiring harness continuity: Measure the wiring harness between the SRS ECU and the left front side curtain airbag. Verify no open circuits, short circuits, or shorts to ground exist.
  • 6
    If the wiring harness resistance is normal, check the seat position sensor (if applicable): measure the 5V sensor power supply, verify the signal voltage varies between 0.5-4.5V with position, and confirm normal ground.
  • 7
    If the wiring harness check shows no faults, perform a substitution test using a known-good airbag module or sensor (operate with caution and disconnect power).
  • 8
    Check the SRS ECU power supply (constant battery positive +B), ground, and CAN communication line voltage.
  • 9
    After repair, reconnect the battery, clear the fault codes, perform an SRS system self-check (turn the ignition switch to the ON position and verify the indicator light turns off), and perform a road test to verify the repair.
Real-World Cases
BYD DTC AI Analysis

BYD Song Pro - Seat rail chafes wiring harness causing B1760 false positive

✓
Airbag warning light remained on after startup. Scan tool retrieved DTC B1760. In the Song Pro, this code actually points to a driver seat position sensor circuit fault. Removing the driver's seat revealed the seat rails had worn through the position sensor wiring harness during fore-aft adjustment. Two of the three internal wires were completely fractured, creating an open circuit that the SRS system reported as "not present". Repaired the broken harness, rerouted it to the outside of the rails and reinforced it with corrugated tubing. Cleared the codes; system returned to normal.
Original source ↗
BYD DTC AI Analysis

BYD Qin Plus DM-i - Sensor connector poor contact

✓
While driving, the dashboard intermittently displayed "Check SRS System". The fault occurred more frequently in rainy or humid weather. The diagnostic scanner detected an intermittent B1760 code. Inspection of the position sensor connector beneath the driver's seat revealed a loose locking tab and internal oxidation. Resistance fluctuated severely when gently shaking the wiring harness. Cleaned the pins with electronic contact cleaner, adjusted the connector locking tab spring, applied conductive grease to enhance waterproofing, and secured the wiring harness with cable ties to eliminate vibration. One month of post-repair monitoring confirmed no recurrence.
Original source ↗
BYD DTC AI Analysis

BYD Tang DM - Seat position sensor unit damaged

✓
Seat memory failed to store positions; the instrument cluster displayed B1760. Autel MS906S live data showed the driver seat fore-aft position signal stuck at 255 (invalid data), unchanged during seat movement. Sensor 5V supply was normal. Fault traced to worn internal sliding resistor film. Replaced the driver seat position sensor assembly (BYD-69F-001), performed sensor zero-point calibration with the special tool, and reset the memory positions. Seat welcome and memory functions returned to normal.
Original source ↗
BYD DTC AI Analysis

BYD Han EV - Factory Assembly Defect on New Car

✓
At 800 km, the airbag warning light suddenly illuminated. The dealership diagnostic tool showed B1760. Inspected the driver seat position sensor and found the fixing clip was not fully engaged (factory assembly defect). A 2–3 mm gap between the sensor and seat rail caused the position detection signal to drift, and the SRS system determined the sensor was "not present". Reinstalled the sensor ensuring the clip fully engaged, added a 1 mm rubber shim to eliminate the gap and dampen vibration, and performed calibration using the diagnostic tool. Repaired free of charge under warranty.
Original source ↗
BYD DTC AI Analysis

BYD Song MAX - Multi-system faults following water ingress

✓
After driving through water, the dashboard simultaneously displayed faults for the airbag, ESP, and tire pressure monitoring systems. The scan tool retrieved multiple DTCs including B1760 and C0035. Inspection under the seat found approximately 5ml of standing water and sediment inside the wiring harness connector; the seat position sensor was shorted to ground. Determined that water ingress caused sensor damage and connector corrosion. Replaced the driver's seat position sensor and the corroded wiring harness connector, thoroughly cleaned and blow-dried the harness, applied waterproof silicone grease to critical connectors, cleared the fault codes, and all systems returned to normal.
Original source ↗
Other Atto 8 Fault Codes
B110811This DTC indicates a short circuit in the air conditioning system PM2.5 air quality sensor (rapid detector). Specifically, abnormal continuity exists between the sensor power supply circuit or signal output circuit and body ground or battery positive. This causes the control module (ACU/air conditioning controller) to detect abnormal current or a voltage signal outside the valid range (typically 0V or supply voltage). The PM2.5 sensor monitors internal and external particulate concentrations, providing the data the automatic air conditioning system uses to switch between fresh air and recirculation modes. A short circuit disables the air quality monitoring function. This fault may force the air conditioning system into recirculation protection mode and trigger related thermal management system faults, as the air conditioning system acts as a key actuator in vehicle thermal management. In severe cases, the short circuit current can damage the internal sampling circuit of the air conditioning controller or overheat the wiring harness.B1109DTC B1109 indicates an open circuit in the communication line between the air conditioning system PM2.5 air quality sensor (dust concentration sensor) and the air conditioning control unit (AC ECU), or an open circuit within the sensor internal circuitry. Typically located in the air conditioning intake duct, this sensor monitors real-time PM2.5 particle concentration inside and outside the vehicle. It provides data to the automatic air conditioning system for intelligent switching between fresh air and recirculation modes and for controlling the air purification device. During an open circuit fault, the AC ECU cannot receive the air quality signal, triggering the system fail-safe mode. Symptoms typically include failure of the automatic recirculation function, abnormal air purification indicator light operation, or abnormal air quality data displayed on the air conditioning panel. Severe cases may compromise the cabin environment control strategy, but do not directly affect vehicle driving safety.B110A02DTC B110A02 indicates the thermal management master control unit (HVAC ECU) or body control module (BCM) failed to receive valid CAN data frames from the PM2.5 air quality sensor over consecutive communication cycles (typically 500ms per cycle). The sensor typically mounts at the HVAC unit air inlet or behind the glove box and transmits real-time particulate concentration data (unit: μg/m³) to the HVAC controller via the CAN bus. The fault is essentially a communication link layer timeout. Potential causes include physical layer wiring faults, sensor power supply failures, sensor internal MCU lockup, or CAN network topology damage. Although this non-critical fault does not directly affect driving safety, it disables the intelligent air purification strategy and the automatic fresh air/recirculation switching function. In extreme cases, it triggers a thermal management system degraded mode, limiting compressor power or fixing the air flap position.B110B07This fault code indicates abnormal operation of the internal air pump (sampling pump) in the PM2.5 air quality detection module. The PM2.5 detector uses the laser scattering principle to measure particulate concentration and requires a built-in air pump to draw ambient air into the detection chamber at a constant flow rate. The ECU sets this code when it detects an open or short in the air pump drive circuit, abnormal current (stall or free-running), or abnormal speed feedback. This fault causes the automatic air conditioning system to lose air quality sensing capability, preventing automatic switching between fresh air and recirculation modes. The instrument cluster air quality display may show '--' or a fixed value, but the fault does not affect the vehicle powertrain or basic air conditioning cooling and heating functions.B173CDTC B173C indicates the Supplemental Restraint System (SRS) detects the Right Second Row Side Airbag squib circuit resistance exceeds the calibrated threshold (typically >4.5Ω). This fault is an active diagnostic result of the SRS system, indicating a high-resistance condition in the circuit between the Airbag Control Unit (ACU) and the airbag module. Causes for excessive resistance include increased contact resistance, a partially broken wiring harness, terminal oxidation, or an aging squib wire inside the airbag module. This fault causes the system to mark the airbag circuit as 'unreliable', meaning the airbag may fail to deploy during a collision. The fault typically illuminates the instrument cluster airbag warning light (SRS light) continuously, and some models also sound a warning buzzer.
Common problems reported for Atto 8 →Atto 8 overview →
Data confidence: Official This information is for reference only. Always consult a qualified technician for diagnosis and repair. Do not attempt high-voltage system repairs yourself.